body {
    background: linear-gradient(to right, #e0eafc, #cfdef3);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 4rem;
}
.payment-container {
    background: white;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    padding: 2rem;
    width: 100%;
    max-width: 1400px;
    text-align: center;
}
.payment-message {
    color: #22c55e;
    font-size: 1.25rem;
    font-weight: bold;
    margin-bottom: 1rem;
}

.payment-btn {
    background: #4facfe;
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 10px;
    margin: 0 1rem;
    transition: background 0.3s;
}

.payment-btn:hover {
    background: #00f2fe;
}

.payment-btn:disabled {
    background: #d1d5db;
    cursor: not-allowed;
}
